ood-ports-lbsd/sysutils/sysclean/pkg/DESCR

sysclean is a script designed to help remove obsolete files between OpenBSD
upgrades.

sysclean compares a reference root directory against the currently installed
files, taking files from both the base system and packages into account.

sysclean does not remove any files on the system. It only reports obsolete
filenames or packages using out-of-date libraries.